Stabilization of Black Cotton Soil Using Ultra Fine Slag

Abstract

The quality and life of pavement is greatly affected by the type of sub-grade, sub base and base course materials. The most important of these are the type and quality of sub-grade soil. But in India most of the flexible pavements are need to be constructed over weak and problematic sub-grade. The California bearing ratio (CBR) of these sub-grades are very low and therefore more thickness of pavement. Decrease in the availability of suitable sub base and base materials for pavement construction have leads to a search for economic methods of improvement of locally available problematic soil to suitable construction materials. The improvement of soil properties is one of the main branches of geotechnical science that has been considered by researchers in different countries. In developing country like India due to the remarkable development in road infrastructure, soil stabilization has become the major issue in construction activity. Stabilization is an unavoidable for the purpose of highway and runway construction, stabilization denotes improvement in both strength and durability which are related to performance. Stabilization is a method of processing available materials for the production of low-cost road design and construction. Fine clayey soils properties due to high swelling necessitate the need to improve its geotechnical properties. Black cotton soils when used as a subgrade for pavements has risks of substantial settlements, heave and low bearing capacity. This project is an investigation carried out to study the effect of Ultra fine slag on engineering and strength properties of the Black Cotton Soils. The properties of stabilized soil such as compaction characteristics, consistency limits, California bearing ratio and swell potential were evaluated and their variations with Ultra fine slag content evaluated. The interpretation of test results leading to various conclusion and recommendation on the use of Ultra fine slag in soil stabilization to counter the difficulty posed by black cotton soil for subgrade material is discussed.